Hello All My first post so please be gentle I'm building a store room extension to a detached double garage. Its dense concrete block construction, 5m x 4m and will have a warm flat roof. I'm planning to run my 75x200 joists from the existing single skin brick wall of the attached garage across to my "new" extension wall. I had planned to install a wall plate (47x100mm) on the concrete blocks, then install the joists on top. However, this would have pushed the roof height about 60cm over the 2.5M planning restrictions so I'm having to save roof height where I can. My thinking is to use Masonary Rapid Build hangars like these; (https://www.secfixings.co.uk/product/rbjhi-rapid-build-joist-hangers/) and hang them down from the top course of blocks, reducing the roof height by 200mm (putting me well within planning restrictions) My question - Can I install these rapid build hangars on top of a wooden wall plate secured to the top course of blocks? I want to do this to add a little bit of lost ceiling height due to not installing the hangars on the top course of blocks. Apologies for the convoluted question... Any insight much appreciated.